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- hostInfo
hostInfo¶
On this page
-
hostInfo
¶ Returns: A document with information about the underlying system that the mongod
ormongos
runs on. Some of the returned fields are only included on some platforms.You must run the
hostInfo
command, which takes no arguments, against theadmin
database. Consider the following invocations ofhostInfo
:db.hostInfo() db.adminCommand( { "hostInfo" : 1 } )
In the
mongo
shell you can usedb.hostInfo()
as a helper to accesshostInfo
. The output ofhostInfo
on a Linux system will resemble the following:{ "system" : { "currentTime" : ISODate("<timestamp>"), "hostname" : "<hostname>", "cpuAddrSize" : <number>, "memSizeMB" : <number>, "numCores" : <number>, "cpuArch" : "<identifier>", "numaEnabled" : <boolean> }, "os" : { "type" : "<string>", "name" : "<string>", "version" : "<string>" }, "extra" : { "versionString" : "<string>", "libcVersion" : "<string>", "kernelVersion" : "<string>", "cpuFrequencyMHz" : "<string>", "cpuFeatures" : "<string>", "pageSize" : <number>, "numPages" : <number>, "maxOpenFiles" : <number> }, "ok" : <return> }
Output¶
-
hostInfo
¶ The document returned by the
hostInfo
.
-
hostInfo.
system
¶ An embedded document providing information about the underlying environment of the system running the
mongod
ormongos
-
hostInfo.system.
currentTime
¶ A timestamp of the current system time.
-
hostInfo.system.
hostname
¶ The system name, which should correspond to the output of
hostname -f
on Linux systems.
-
hostInfo.system.
cpuAddrSize
¶ A number reflecting the architecture of the system. Either
32
or64
.
-
hostInfo.system.
memSizeMB
¶ The total amount of system memory (RAM) in megabytes.
-
hostInfo.system.
numCores
¶ The total number of available logical processor cores.
-
hostInfo.system.
cpuArch
¶ A string that represents the system architecture. Either
x86
orx86_64
.
-
hostInfo.system.
numaEnabled
¶ A boolean value.
false
if NUMA is interleaved (i.e. disabled), otherwisetrue
.
-
hostInfo.
os
¶ An embedded document that contains information about the operating system running the
mongod
andmongos
.
-
hostInfo.os.
type
¶ A string representing the type of operating system, such as
Linux
orWindows
.
-
hostInfo.os.
name
¶ If available, returns a display name for the operating system.
-
hostInfo.os.
version
¶ If available, returns the name of the distribution or operating system.
-
hostInfo.
extra
¶ An embedded document with extra information about the operating system and the underlying hardware. The content of the
extra
embedded document depends on the operating system.
-
hostInfo.extra.
cpuString
¶ A string containing a human-readable description of the system’s processor.
cpuString
only appears on macOS systems.
-
hostInfo.extra.
versionString
¶ A complete string of the operating system version and identification. On Linux and macOS systems, this contains output similar to
uname -a
.
-
hostInfo.extra.
libcVersion
¶ The release of the system
libc
.libcVersion
only appears on Linux systems.
-
hostInfo.extra.
kernelVersion
¶ The release of the Linux kernel in current use.
kernelVersion
only appears on Linux systems.
-
hostInfo.extra.
alwaysFullSync
¶ alwaysFullSync
only appears on macOS systems.
-
hostInfo.extra.
nfsAsync
¶ nfsAsync
only appears on macOS systems.
-
hostInfo.extra.
cpuFrequencyMHz
¶ Reports the clock speed of the system’s processor in megahertz.
-
hostInfo.extra.
cpuFeatures
¶ Reports the processor feature flags. On Linux systems this the same information that
/proc/cpuinfo
includes in theflags
fields.
-
hostInfo.extra.
pageSize
¶ Reports the default system page size in bytes.
-
hostInfo.extra.
physicalCores
¶ Reports the number of physical, non-HyperThreading, cores available on the system.
physicalCores
only appears on macOS systems.
-
hostInfo.extra.
numPages
¶ numPages
only appears on Linux systems.
-
hostInfo.extra.
maxOpenFiles
¶ Reports the current system limits on open file handles. See UNIX ulimit Settings for more information.
maxOpenFiles
only appears on Linux systems.
-
hostInfo.extra.
scheduler
¶ Reports the active I/O scheduler.
scheduler
only appears on OS X systems.